Overhead-valve engine



Jan. 21, 1930. A, c v o -r 1,744,526

OVERHEAD VALVE ENGINE Filed March 1 928 IN VEN TOR.

fixmw? E f/rfmazfz Patented Jan. 21, 1930 ,744,526

UNITED STATES RATENT FFIE ARTHUR E. CHEVROLET, OF INDIANAPOLIS, INDIANA.

OVERHEAD-VALVE ENGINE Application filed. March 1, 1928. Serial No. 258,333.

This invention relates to an adaptor for 19. the stems by the numeral 20, the springs obtaining greater efficiency in a combustion associated therewith by the numeral 21 and chamber. the retainers generally by the numeral 22.

The chief object of this invention 1s to All of the aforesaid constitutes a convenpermit engine operation at relatively higher tional over-head valve type motor. 55

compressions, to obtain greater economy. The invention contemplates the mounting power and efficiency and eliminate the usual within each cylinder or in the combustion accompanying objectionable detonation and chamber in the head, if suiiicient space is to obtain turbulence of the fuel in the cylprovided, of means for dividing the cylinder and combustion chamber. inder space or combusion chamber into two so The chief feature of the invention conchambers having relatively restricted comsists in the accomplishment of the foregoing munica'tion and forming the surfaces of the object by the provision .of a restriction of restricting means such that predetermined suitable conformation in the head of the cylfuel flow obtains, towit, turbulence. The reinder or adjacent thereto and adjacent valves striction eliminates detonation and provides 65 of an over-head valve type engine. relatively lar e bodies of metal at the throat Another feature of the invention not only of the restriction so that there will be no glow consists in the formation of the same as an points and therefore there will be no preadaptor unit, that is, one that may be readignition from this cause, if and when the ily applied to the cylinder engines previously compression is increased by the introduction 70 constructed for transforming them, but the of a volume reducing member. particular shape of the adaptor restriction The present form of the invention is illusconstitutes another feature. trated as an adaptor unit for a standard The full nature of the invention will be overhead valve-type engine. The adaptor 5 understood from the accompanying drawings consists of a tubular member having a re 75 and the following description and claims: stricted opening eccentric of the cylinder in the drawings Fig. 1 is a longitudinal 11 or combustion chamber. The body porcentral sectional view of two adjacent cyl tion forming the restriction includes a relinders of a multi-cylinder ove -head valve atively steep wall or surface 26 and a reltype engine. Fig. 2 is an enlarged top plan ativ-ely flat but elongated surface 27 and 28 so view of the adaptor unit. Fig. 3 is an enforming a tongue 29 or partition therebelarged vertical sectional view taken in a tween. It will be noted that the remote wall plane of ninety degrees to the section shown portion 26 from substantially the mid-porin Fig. l and on the section line 38 of Fig. tion or thereabouts, is flared outwardly in 2 with the unit in position in a cylinder. both directions, the slopes being opposed and $5 In the drawings there is illustrated two quite steep, while the opposite baiile porcylinders of multi-cylinderengine,the cyltion is of double incline or Wedge shape. inders being indicated by the numeral 10 Each two opposed slopes of the partiand a combustion space 11 in each of which tion merge into each other, as shown per i0 is mounted the piston 12 having rings 13 ticularly in Figs. 2 and 3, with what and connecting rod 1d. Mounted upon the might be termed an arcuately sectioned wall cylinder block 10 is a head construction 15 forming the throat, the radius of which inhaving a water cooling space 16 and suitable creases for the portions more remote from the gasket means 17 may be interposed between axis. Thesubstantially cylindrical exterior 45 the block and head, if and when desired. wall 30 at opposite sides is cut away at 31 to Herein each cylinder is shown provided with provide for valve clearance permitting the a pair of valves, one of which is the exhaust valves to move into the cylinder or combusvalve and the other of which is the intake tion chamber when opened. The adaptor valve. The valves are indicated by the numay be press fitted into the combustion charm to meral 18, the valve seats 33* the numeral her or otherwise secured, as shown particular- 1G0 ly in Fig. 3 where headless set screws 40 are mounted in the adaptor and engage the adjacent cylinder wall.

Upon the intake stroke part of the gas, it will be apparent, discharges directly through opening 25, while the remainder of the gas engages the upper inclined surface adjacent the restriction and is caused to swirl before it can pass through the opening 25. In other words, there is created a turbulent condition in the fuel upon the intake thereof. Also by reason of the reverse curvature or multiple inclination construction, upon the compression stroke the gas is forced from the cylinder into the chamber above the partition 29 and with a swirling motion similar to that obtained upon the intake so that turbulence is again obtained and the adaptor, therefore, secures multiple turbulence. The result is greater economy, greater power, greater eiiiciency and no detonation. The objection to increasing the compression of a standard overhead valve-type engine is that the same is liable to cause detonation and pre-ignition, or both. Vith the present invention high compressions can be utilized Without detonation and pie-ignition occurring. There is no glow point in the device, which, when heated to the engine temperature, will preignite the mixture prior to firing by the plug. Also when the mixture is fired the same or initial explosion takes place in the restricted chamber above the cylinder chamber proper and as the combustion increases the flame passes through the throat defined by opening 25 and the remainder of the gas burns. The result is a long and steady burning which has the exact opposite attributes from that of detonation and as a result there is a longer and substantially continuous application of power to the head of the piston, by reason of the longer burning of the gas and as a result greater force (of expansion) is exerted upon the piston.

The present invention, therefore, not only diminishes the strength of the initial explosion, and therefore eliminates detonation, but secures a uniform andreadily combustible fuel mixture in substantially vapor form by reason of the double swirling, that is the swirling upon the intake and the swirling upon the compression strokes of the engine.

While the invention is herein disclosed as an adaptor, it is to be understood that the same may be cast integral with either the cylinder head or the block ora part in both and the water cooling jacket space extenoed into the metalforming the restriction to water cool the same.

The invention claimed is:

1. In an overhead valve, high compres sion, internal combustion engine, the. combination with a substantially cylindrical cylinder, a piston therein, a head portion for the. cylinder, andvalves mountedin said: head portion controlling intake and exhaust to and from said cylinder respectively, of a turbulence producing partition portion reducing the clearance volume of the engine, said partition including an aperture therethrough, said aperture being positioned eccentrically of the cylinder axis, the opposite surfaces of the partition sloping from the cylinder to wards the aperture in inclined relation and merging at the aperture, said partition obtaining turbulence upon the intake and compression periods of engine operation.

2. In an overhead valve, high compression, internal combustion engine, the combination with a substantially cylindrical cylinder, a piston therein, a head portion for the cylinder, and valves mounted in said head portion controlling intake and exhaust to and from said cylinder respectively, of a turbulence producing partition portion reducing the clearance volume of the engine, said partition including an aperture therethrough, said aperture being positioned eccentrically of the cylinder axis, the opposite surfaces of the partition sloping from the cylinder towards the aperture in inclined relation and merging at the aperture with a substantially arcuate cross-sectioned wall forming the throat of the aperture, said partition obtaining turbulence upon the intake and compression periods of engine operation.

3. In an overhead valve, high compression, internal combustion engine, the combination with a substantially cylindrical cylinder, a piston therein, a head portion for the cylinder, and valves mounted in said head portion controlling intake and exhaust to and from said cylinder respectively, of a turbulence producing partition portion reducing the clearance volume of the engine, said partition including an aperture therethrough, said aperture being positioned eccentrically of the cylinder axis, the opposite surfaces of the partition sloping from the cylinder towards the aperture in inclined relation and merging at the aperture, the portions of the partition surfaces more remote from the axis having a greater slope than the diametrically opposite portions, said partition obtaining turbulence upon the intake and compression periods of engine operation.

a. In an overhead valve, high compression, internal combustion engine, the combination with a substantially cylindrical cylinder, a piston therein, a head portion for the cylinder, and valves mounted in said head portion controlling intake and exhaust to and from said cylinder respectively, of a turbulence producing partition portion reducing the clearance volume of the engine, said partition including an aperture therethrough, said aperture being positioned eccentrically of the cylinder axis, the opposite surfaces of the partition sloping from the cylinder towards the aperture in inclined relation and merging at the aperture, the partition surface adjacent the head having a greater slope than the longitudinal opposite portion of the surface adjacent the piston, said partition obtaining turbulence upon the intake and compression periods of engine operation.

5. In an overhead valve, high compression, internal combustion engine, the combination with a. substantially cylindrical cylinder, a piston therein, a head portion for the cylinder, and valves mounted in said head portion controlling intake and exhaust to and from said cylinder respectively, of a turbulence producing partition portion reducing the clearance volume of the engine, said partition including an aperture therethrough, said aperture being positioned eccentrically of the cylinder axis, the opposite surfaces of the partition sloping from the cylinder towards the aperture in inclined relation and merging at the aperture, the portions of the partition surfaces more remote from the axis having a greater slope than the diametrically opposite portions, the partition surface adjacent the head having a greater slope than the longitudinal opposite portion of the surface adjacent the piston, said partition obtaining turbulence upon the intake and compression periods of engine operation.

6. In an overhead valve, high compression, internal combustion engine, the combination with a substantially cylindrical cylinder, a piston therein, a head portion for the cylinder, and valves mounted in said head portion controlling intake and exhaust to and from said cylinder respectively, of a turbulence producing partition port-ion reducing the clearance volume of the engine, said partition including an aperture therethrough, said aperture being positioned eccentrically of the cylinder axis, the opposite surfaces of the partition sloping from the cylinder towards the aperture in inclined relation and merging at the aperture with a substantially arcuate cross-sectioned wall forming the throat of the aperture, the portions of the partition surfaces more remote from the axis having a greater slope than the diametrically opposite portions, said partition obtaining turbulence upon the intake and compression periods of engine operation.

7. In an overhead valve, high compression, internal combustion engine, the combination with a substantially cylindrical cylinder, a piston therein, a head portion for the cylinder, and valves mounted in said head portion controlling intake and exhaust to and from said cylinder respectively, of a turbulence producing partition portion reducing the clearance volume of the engine, said partition including an aperture therethrough, said aperture being positioned eccentrically of the cylinder axis, the opposite surfaces of the partition sloping from the cylinder towards the aperture in inclined relation and merging at the aperture with a substantially arcuate cross-sectioned wall forming the throat of the aperture, the partition surface adjacent the head having a greater slope than the longitudinal opposite portion of the surface adjacent the piston, said partition obtaining turbulence upon the intake and compression periods of engine operation.

8. In an overhead valve, high compression, internal combustion engine, the combination with a substantially cylindrical cylinder, a piston therein, a head portion for the cylinder, and valves mounted in said head portion controlling intake and exhaust to and from said cylinder respectively, of a turbulence producing partition portion reducing the clearance volume of the engine, said partition including an aperture therethrough, said aperture being positioned eccentrically of the cylinder axis, the opposite surfaces of the partition sloping from the cylinder towards the aperture in inclined relation and merging at the aperture with a substantially arcuate cross-sectioned wall forming the throat of the aperture, the portions of the partition surfaces more remote from the axis having a greater slope than the diametrically opposite portions, the partition surface adjacent the read having a greater slope than the longitudinal opposite portion of the surface adjacent the piston, said partition obtaining turbulence upon the intake and compression periods of engine operation.

9. In an overhead valve, high compression, internal combustion engine, the combination with a substantially cylindrical cylinder, a piston therein, a head portion for the cylinder, and valves mounted in said head portion controlling intake and exhaust to and from said cylinder respectively, of a turbulence producing partition portion reducing the clearance volume of the engine, said partition including an aperture therethrough, said aperture being positioned eccentrically of the cylinder axis, the opposite surfaces of the partition sloping from the cylinder towards the aperture in inclined relation and merging at the aperture, said partition portion at the sides immediately adjacent the cylinder wall being suitably relieved for valve clearance, said partition obtaining turbulence upon the intake and compression periods of engine operation.

In witness whereof, I have hereunto affixed by signature.

ARTHUR E. CHEVROLET. 

